Sickle drive



y 1958 I. c. ROGERS ETAL I 2,835,133

SICKLE DRIVE Filed Jan. 6, 1955 2 Sheets-Sheet 1 INVENTORS Ivor C;Rogers leonard- M. Jmuse May 20, 1958 SICKLE DRIVE Filed Jan. 6, 1955 2Sheets-Sheet 2 a m y 1 f. a a & 1i is {L n d .Hh. 5% fi I a E 1|1-\\ Q I@Q am H a v A a M 4 A 1 H. |F|//r\\ mm m y mm z t HUI C: M F S k WW/54?w W 2 k A .wfl Nb wN mm.

2,835,133 Patented May 20, 1958 SICKlLE DRIVE Ivor C. Rogers and LeonardM. Krause, Toronto, On-

tario, Canada, assignors to Massey-Harris-Ferguson Limited, Toronto,Ontario, Canada, a corporation of Canada Application January 6, 1955,Serial No. 480,167

3 Claims. (Cl. 74--60) This invention relates to reciprocating cuttermecha nisms for severing a growing crop. It relates, more specifically,to a sickle drive of the wobble type and finds particular utility inagricultural machines such as mowers, harvesters and the like.

It is an object of this invention to provide an improved wobble drivefor a reciprocating knife, commonly referred to as a sickle.

It is a more specific object of this invention to provide a whole drivesickle having means for restricting the rotative input motion to onedirection, namely, a purely reciprocatory direction of the knift; thetwisting moment due to the rotation of the input drive is absorbed bythe main frame which supports the drive mechanism.

It is another object of the invention to provide an improved knife drivewhich eliminates, to a substantial degree, friction and consequent wearon the knife, knife guides, wear plates and holddown clamps and resultsin a highly efiicient knife drive requiring a minimum of adjustment andservicing. a

It is still another object of this invention to provide a highly compactknife drive mounted to supporting structure in such a manner so as tolocalize any vibratory forces which may occur and prevent them frombeing transmitted to other component parts of the machine.

It is another object of this invention to provide a knife drive unit andits associated knife which are mounted directly and solely on a supportmeans which also supports the coacting guards which results in beingable to accurately register the coacting parts of the cutting mechanism,within manufacturing tolerances, and maintain such registry withoutfurther adjustment once the initial alignment has been made.

It is still another object of the invention to provide a relativelysimple knife drive which is economical to manufacture and eificient inperforming the functions for which it is designed.

Other objects and advantages of this invention will becomemore apparentas this disclosure progresses, reference being had to the accompanyingdrawing, in which:

Figure 1 is an elvational end view from the inner, or knife, side of themechanism, with certain parts in section and parts broken away. Thisview is taken on the line 1-1 of Figure 2.

Figure 2 is an elevational front view of the device shown in Figure 1partially in section, with certain parts removed for the sake ofclarity.

, Figure 3 is a plan view, on an enlarged scale, with certain parts ofthe driving mechanism removedfor the sake of clarity.

Figure 4 is an elevational end view, on an enlarged scale, from theouter side of the mechanism, partially in section, and certain partsremoved for clarity in the drawings.

Figure 5 is a view of the driving shaft, in the same position itoccupies in Figure 2, but on a reduced scale.

Figure 6 is a view of the reciprocating member, in the same position itoccupies in Figure 2, but on a reduced scale.

The mechanism to which this invention relates is generally carried by asupporting framework at the forward end of an agricultural machine andat a substantially constant attitude to the ground over which ittraverses. This frame may be of any suitable design and in thisembodiment is shown in Figure 1 as comprising angle member 10, supportmember 12, laterally extending plate 14 and a ground engaging shoe 16all of which are rigidly secured together to form a supporting structureor frame.

Wobble drive means The support for the drive is in the form of a housing18 having a pedestal portion 20 which is secured by cap bolts 22 passingthrough apertures 23 and threadably engaging plate 14, and also by bolts24 extending through plate 14 and engaging nuts 25. The upper portion ofhousing 18 has a bore 26 extending therethrough (Figure 2). Counterbores27 and 28 at either end of bore 26 form seats for the outer races 33a ofthe roller bearing assemblies 33. These anti-friction bearings take theaxial thrust in either direction on the shoulders 31, 32 which areformed by bores26, 27 and 28. Outwardly extending arms 34, 35 form arigid bracket support and each have a bore 34a, 35a, respectively (Fig.4) in their free end in which is mounted anti-friction ball bearingassemblies 37, 38 respectively.

An input drive shaft 40 is rotatably mounted within bore 26 in bearingassemblies 33. An inner end cap 41 is mounted on a reduced portion 42 ofshaft 40 and has a driving sprocket 43 rigidly secured thereto. A capbolt 44 extends through cap 41 and is threadably engaged in a tappedhole 45 in the end of shaft 40, thus securing shaft 40 within housing 18from axial displacement in one direction. Inner surface 46 of cap 41bears against the shoulder 40 (Fig. 5) formed between the shaft 40 andreduced portion 42 which prevents bolt 44 from drawing cap 41 tootightly against housing 18 and insures a free running fit between theouter annual flange 48 of cap 41 and housing 18. The outer end of shaft40 is formed with a shaft portion 50 which is eccentric or offset at anangle to the axis of shaft 40. Annular flange 52, which is formed as anintegral part of shaft 40, serves to enclose the outer side of housing18 in the same manner as does flange 48. The shaft 40 is thus enclosedwithin housing 18 on anti-friction bearings which are sealed fromforeign matter such as dust and dirt. Power is supplied to thismechanism through sprocket 43.

Reciprocating member A reciprocating member is mounted on shaft portion50 and comprises a collar portion 57 (Fig. 2) mounted on ball bearingassembly 59 carried on shaft portion 50, and a downwardly extending armportion 60 formed integral with collar 57. Bearing assembly 59 isretained on a reduced portion 61 of shaft 56 by means of a washer 62 andnut 63 threadably engaged on shaft 50. An outer cover 64 is secured bybolt and nut means 65 to collar 57 and has an annular flange 67 whichbears against, and prevents axial displacement of, the bearing assembly59.

Intermediate member Downwardly extending arm 60 is connected to thereciprocable knife 70 by an intermediary which takes the 'form of aswinging yoke 72.

3; The upper ends of arms 74, 75 are spaced apart sufficiently so as toresist any twisting moment in a plane containing it and to insure thatthe yoke 72 is capable of only oscillatory movement in the direction ofknife travel as shown by the curvilinear arrows in Fig. 2.

The lower bightportion 800i yoke 72 "has a recess 82 (-Fig. 4) intowhich is inserted theball bearing assembly 84. Assembly 84 receives. thelower free end of arm 61 and as the latter, is drivingly oscillated, theyoke 72 oscillates. therewith.

Cutting mechanism Alug 86 having an aperture 860: (Fig. 4) therethroughextends downwardly from yoke 72 and is secured to the knife connector,or clevis, 88 by nut and bolt means. 89 extending therethrough. Clovis8.8. issecured to the leaf spring 69 and cutter bar 70 of the knifeassembly by rivets 8.7.

The cutter bar 70 has secured along its length the con.- ventional knifesections 71 by means of rivets 74a. Conventional knife guides 76. aresecured along the length at spaced locations, of plate 14 and extendover the knife as shown in Figure 1. A wear plate 76 is secured alongthe length of the forward edge of plate 1.4 and absorbs the rearwardthrust of the knife assembly through cutter bar 70. Knife guards 78having ledger plates 78' secured therein, are also secured along thelength of plate 14 by means of the. bolts. 7.9 (Fig. 3). A hold downclamp 81 is secured by cap bolts'83: to the horizontally disposed plate85 which in turn is rigidly mounted on plate 14 by bolts 24 and nuts 25.The rear- Ward end 81 of clamp 81 bears against thetop surface of theend knife section 72 and acts to hold it down in sliding engagementtherewith. It is important that the knife sections 71 register properlywith the guards 78 for proper cutting and to maintain such registry hasbeen a troublesome matter in the past. With the present invention,however, both the knife sections 71 and the guards 78 are accuratelylocated with respect to each other because of the fact that themounting, or pedestal, 20 and the guards 78 are both secured to a commonplate 14. Therefore, the spacing of the holes in which guards 78 andpedestal 20 are secured can be held within close manufacturingtolerances and registry of these parts assured. In other words thepivotal point 85 is fixedly located with respect to the knife guards'78. Furthermore, point 85 is located very closely to the knife in avertical direction and therefore the moment arm or driv ing couple isminimized; furthermore, arcuate movement of. point 89 is negligible. Itwill be noted that the entire drive unit is located in the same verticalplane as the driven knife.

By so mounting this compact drive unit any knife unbalance is confinedto the cutter bar and drive itself and is not transmitted to otherintermediate support members.

Operation In operation, power is supplied through a flexible belt suchas a chain (not shown) to sprocket 43 which causes shaft 4.0 and itseccentric portion 50 to rotate therewith.

The wobble motion of eccentric shaft 50 is translated into a swingingmotion of the arm 60 and in addition there is a considerable rotativeforce on arm 60 tending to make it rotate in the direction in which theshaft 40 is driven. If the lower. end of reciprocating member 60 wasconnected directly to the knife head, this tendency 4 to rotate, wouldcause considerable friction, and wear between the wear plate 76 andcutter bar 70, knife sections 71, guides 76, guards 78 and ledger plates78. These frictional forces are of considerable magnitude in high-speedcutters of this type and cause this type of mechanism to requirefrequent adjustment, alignment and servicing. However, by the use of anintermediate member, such as the yoke 72, the rotative force or twistingmoment' on the'knife due to the rotating input shaft 40 is absorbed inthe drive housing 18. The rotative force from the input shaft 40 istransmitted through the reciprocating member 60 to the yoke 72 and backto the arms 34, 3.5 of the housing 18. Only a truly reciprocatory motionin the direction of intended travel is imparted to the knife. After theinitial alignment of the knife and its associated parts is made and theknife sections brought into proper registry with the guards, littleattention or servicing is required thereafter.

What we claim and desire to secure by; Letters Patent 1.. A drivemechanism. for a reciprocating type cutter comprising; a support frame,a housing rigidly mounted onzsaidframe. and having spaced bracket armsextending in one. direction, wobble means rotatably mounted in saidhousing, means to drive said wobble means, a member rotatably mounted onsaid wobble means and having a downwardly extending arm, a yoke memberhaving spaced arms-pivotally secured to said bracket arms and having adownwardly extending portion operatively con nected with said downwardlyextending arm for oscillation therewith, said portion adapted to bepivotally connected with said cutter.

2. A drive mechanism for a reciprocating type cutter comprising; asupport frame, a housing rigidly mounted on said frame and having spacedbracket arms extending in one direction, wobble means rotatably mountedin said housing, means to drive said wobble means, a member having acollar portion rotatably mounted on said wobble. means and having adownwardly extending arm, a yoke member having spaced arms pivotallysecured to said bracket arms and having a downwardly extending portionoperatively connected with said downwardly extending arm for oscillationtherewith, said portion adapted to be pivotally connected with saidcutter.

3. A drive mechanism for a reciprocating type cutter comprising; asupport frame, a housing having a bore extending therethrough and alsohaving spaced bracket arms extending in one direction, said housingsecured to said frame, wobble means comprising a shaft rotatably mountedin said bore and having an eccentric part, means to drive said wobblemeans, a member having a collar portion rotatably mounted on saideccentric part and having a downwardly extending arm, a yoke memberhaving spaced arms pivotally secured to said bracket arms and having adownwardly extending portion operatively connected with said downwardlyextending arm for oscillation therewith, said portion adapted to bepivotally connected with said cutter.

References Cited in the file of this patent UNITED STATES PATENTS1,390,890 Dyer Sept. 13, 1921 1,997,279 Chilton Apr. 9, 1935 2,258,517Rose Oct. 7, 1941 2,302,995 Holmes Nov. 24, 1942 2,619,839 Love Dec. 2,1 2

